Several Q&A sheets about different aspects of vaccines and vaccine safety are available on the Educational Materials page of our website.

Deciding whether to alter the immunization schedule

In this age of choices about everything from which songs are on our personal listening devices to which custom drinks we want at the local coffee shop, we are used to deciding what we want and don’t want for ourselves and our families. This notion has also started to pervade healthcare. For example, some parents now feel they should approach the childhood immunization schedule in an a la carte manner, giving their children only those vaccines that they feel are appropriate.

While this may seem reasonable, sometimes these individual decisions are not based on complete information or follow false logic. If you are considering picking and choosing which vaccines to give your child, please consider the following:

Evaluate each disease fairly – Of course all diseases are not created equal. Some are very scary, some are more deadly, and some are more easily spread. Unfortunately, the ones that are deemed less scary, less deadly, or less infectious may seem like good candidates to forego when choosing vaccines. This kind of logic is like deciding only to treat one’s cancer if it is more deadly or affecting a certain part of the body. The fact of the matter is that every type of cancer—and every vaccine-preventable disease—can kill. Whether the death rate is 1 in 100 or 1 in 10,000, we can’t predict who will be spared and who will not.

Consider whether vaccine immunity is “good enough” – When the disease is considered to be mundane, some parents would rather their children experience the infection rather than the vaccine, especially since diseases often create stronger immunity than vaccines. In addition to the fact that the disease is not mundane for everyone, the fact is that vaccine-induced immunity is typically good enough without paying the price for natural infection. You might think of it like filing taxes; if you can file the 1040EZ and get the same refund, why use the 1040A?

Realize the full scope of the “wait and see” approach - When a new vaccine is developed, some people prefer to delay using it in order to make sure that it works well and is safe. However, each vaccine must be extensively tested before being added to the schedule and millions of vaccines are given by the approved schedule each year. On the other hand, when people arbitrarily make a schedule based on personal preferences, they are essentially subjecting their children to a vaccine without the benefit of data. In one case, the vaccines are delayed to “wait and see” if they are safe despite the existence of data from tens of thousands of people and years of studies. In the other case, the vaccines are given without the benefit of previous experience or data creating a potentially dangerous “wait and see” situation.

Understand the importance of timing – Many parents focus on the number of vaccines given at a single visit and understandably feel that there are too many given at once, particularly for younger infants. However, three issues should be considered:

Vaccines are added to the schedule based on when an infant is likely to be most susceptible to the disease - During the first few months of life, babies are somewhat protected from infectious diseases by maternal antibodies present in their bloodstream at birth or in their mother’s milk; however, protection afforded by maternal antibodies wanes during the first year of life and is somewhat variable. For example, studies have shown that maternal antibody levels in infant blood increase right before delivery, so babies who are born prematurely tend to have lower levels than their full-term counterparts.

Because the length of protection and robustness of the maternal response cannot be predicted, maturing the infant’s own immune response before the maternal response wanes is the most conservative approach. You might think of it like replacing the 15-year-old water heater before the water is flooding your house.

Because most vaccines require more than one dose, limiting the number given at one appointment makes getting all of the doses in a timely manner a tremendous feat – A small percentage of parents have willingly scheduled monthly visits to the doctor’s office in order to give only one or two vaccines to their child at a time. This is similar to the difference between going to the grocery store every day to get the ingredients for dinner and getting a single order on the weekend; in the long run, you have accomplished the same thing, but you’ve probably spent less time and money if you used the latter plan. Unfortunately, when it comes to childhood vaccines, the decision goes beyond time and money because children who are given vaccines one or two at a time are vulnerable to some diseases longer and, may experience more stress. Specifically, in a study completed a few years ago, children given multiple vaccines at once did not experience more pain than children given only a single shot, so multiple visits to the doctor would cause more pain over the long term.

If a baby is not too young to get the disease, she is not too young to get the vaccine – All vaccines expose recipients to a smaller number of antigens, parts that generate an immune response, than the actual pathogen. Even when multiple vaccines are given together, the number of antigens is limited compared with the number of pathogens to which infants are exposed during a normal day. The difference is we know when our children were exposed to antigens through a vaccine, but we aren’t always aware of their exposures to diseases.

Consider ingredients in the appropriate context – Many vaccine-related concerns center on the ingredients that are in vaccines. Contemplating giving our children aluminum, mercury, formaldehyde or any of the other oft-mentioned chemicals in vaccines can be scary; however, thinking about what is in a vaccine should be kept in perspective. For example, consider how we have all become adept at reading nutrient labels; ingredients like unsaturated, polyunsaturated, and trans fats are all in many foods; however, we evaluate the foods based on the quantities of these items. The same should be true for vaccines; the quantities of ingredients in vaccines are not sufficient to cause harm even when multiple vaccines are given at the same time.

Vaccines are arguably the safest, best-tested products we put into our bodies, so the choice not to get them is a choice to take a different and much more potentially serious risk.

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